... transformer coil former 1.features: coil and transformer bobbins,coil with led light,bobbin core coil,transformer coil ... 20 to 80kHz Frequency Range,switching power supply, PCB, STB and other communication and medical equipments;EE,EI Type Transformer ... good shielding quality.Application: Wave carrier filter, power-transfer transformer and aux-power transformer.ER Type TransformerFeature: Compact, low ...